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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Contemporary Mathematics. Fundamental Directions</journal-id><journal-title-group><journal-title xml:lang="en">Contemporary Mathematics. Fundamental Directions</journal-title><trans-title-group xml:lang="ru"><trans-title>Современная математика. Фундаментальные направления</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2413-3639</issn><issn publication-format="electronic">2949-0618</issn><publisher><publisher-name xml:lang="en">Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">30082</article-id><article-id pub-id-type="doi">10.22363/2413-3639-2021-67-4-766-782</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Articles</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Статьи</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Fokas Method for the Heat Equation on Metric Graphs</article-title><trans-title-group xml:lang="ru"><trans-title>Метод Фокаса для уравнения теплопроводности на метрических графах</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Sobirov</surname><given-names>Z. A.</given-names></name><name xml:lang="ru"><surname>Собиров</surname><given-names>З. А.</given-names></name></name-alternatives><email>z.sobirov@nuu.uz</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Eshimbetov</surname><given-names>M. R.</given-names></name><name xml:lang="ru"><surname>Эшимбетов</surname><given-names>М. Р.</given-names></name></name-alternatives><email>mr.eshimbetov92@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">National University of Uzbekistan named after M. Ulugbek</institution></aff><aff><institution xml:lang="ru">Национальный университет Узбекистана им. М. Улугбека</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2021-12-30" publication-format="electronic"><day>30</day><month>12</month><year>2021</year></pub-date><volume>67</volume><issue>4</issue><issue-title xml:lang="en">Science — Technology — Education — Mathematics — Medicine</issue-title><issue-title xml:lang="ru">Наука — технология — образование — математика — медицина</issue-title><fpage>766</fpage><lpage>782</lpage><history><date date-type="received" iso-8601-date="2022-01-24"><day>24</day><month>01</month><year>2022</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2022, Contemporary Mathematics. Fundamental Directions</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2022, Современная математика. Фундаментальные направления</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="en">Contemporary Mathematics. Fundamental Directions</copyright-holder><copyright-holder xml:lang="ru">Современная математика. Фундаментальные направления</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc-nd/4.0/deed.en</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/CMFD/article/view/30082">https://journals.rudn.ru/CMFD/article/view/30082</self-uri><abstract xml:lang="en"><p style="text-align: justify;">The paper presents a method for constructing solutions to initial-boundary value problems for the heat equation on simple metric graphs such as a star-shaped graph, a tree, and a triangle with three converging edges. The solutions to the problems are constructed by the so-called Fokas method, which is a generalization of the Fourier transform method. In this case, the problem is reduced to a system of algebraic equations for the Fourier transform of the unknown values of the solution at the vertices of the graph.</p></abstract><trans-abstract xml:lang="ru"><p style="text-align: justify;">В работе дан метод построения решений начально-краевых задач для уравнения теплопроводности на простых метрических графах, таких как звездообразный граф, дерево и треугольник с тремя сходящимися ребрами. Решения задач построены так называемым методом Фокаса, который является обобщением метода преобразования Фурье. При этом задача сведена к системе алгебраических уравнений относительно преобразования Фурье неизвестных значений решения в вершинах графа.</p></trans-abstract><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Волкова А. С. Обобщенные решения краевой задачи для уравнения теплопроводности на графе// Вестн. СПб. ун-та. Сер. 10. Прикл. матем. Информ. 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